Matthew R. Callstrom, M.D., Ph.D. (IMAGE) Mayo Clinic Caption Matthew R. Callstrom, M.D., Ph.D. Credit Mayo Clinic Usage Restrictions May use with credit License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.